This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. To determine if the site of immunization influences the mucosal homing properties of virus-specific T cells, and protection against a mucosal challenge, separate groups of rhesus macaques were immunized by intravenous versus subcutaneous routes of inoculation with VSV G trans-complemented single-cycle SIV, and challenged by intrarectal inoculaton with wild-type SIV.